U.S. patent number 6,519,878 [Application Number 09/834,925] was granted by the patent office on 2003-02-18 for shoe soles.
This patent grant is currently assigned to Miyata Co., Ltd.. Invention is credited to Miyata Yoshiaki.
United States Patent |
6,519,878 |
Yoshiaki |
February 18, 2003 |
Shoe soles
Abstract
A shoe sole having a resilient outsole including a weight for
applying a larger-than-normal load on the leg muscles. The outsole
has a single recess formed on the upper surface thereof and
extending in a lengthwise direction from a toe portion to a heel
portion of the outsole. The recess has an outline that is similar
to the outline of the outsole and a single weight is embedded in
the recess. The single weight comprises a mixture of a resilient
material and metallic grains and has an outline that is similar to
the outline of the outsole. The weight is formed so as to be
relatively thin at the toe portion and relatively thick at the heel
portion.
Inventors: |
Yoshiaki; Miyata (Osaka,
JP) |
Assignee: |
Miyata Co., Ltd. (Osaka,
JP)
|
Family
ID: |
18806201 |
Appl.
No.: |
09/834,925 |
Filed: |
April 16, 2001 |
Foreign Application Priority Data
|
|
|
|
|
Oct 27, 2000 [JP] |
|
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2000-329545 |
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Current U.S.
Class: |
36/132; 36/136;
482/79; 482/93 |
Current CPC
Class: |
A43B
13/125 (20130101); A43B 13/187 (20130101); A43B
19/005 (20130101) |
Current International
Class: |
A43B
13/18 (20060101); A43B 005/00 (); A43B 023/00 ();
A63B 023/08 (); A63B 021/06 () |
Field of
Search: |
;36/132,136
;482/79,83,105,93 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Stashick; Anthony D.
Attorney, Agent or Firm: Wenderoth, Lind & Ponack,
L.L.P.
Claims
What is claimed is:
1. A shoe sole comprising: a resilient outsole having in a
lengthwise direction from a toe portion to a heel portion of said
resilient outsole, said recess having an outline that is similar to
an outline of said resilient outsole; and a single integral weight
inserted in said recess of said resilient outsole, said weight
comprising a mixture of metallic grains and a resilient material,
wherein said weight comprises a resilient housing filled with said
mixture of metallic grains and resilient material, wherein said
resilient housing comprises a container having an open top, and a
closure bonded to the container, and wherein a bottom surface of
said container is adhesively bonded in said recess of said outsole
to secure the weight therein.
2. A shoe sole as claimed in claim 1, wherein said single weight
fits in said recess and has an outline that is similar to the
outline of said resilient outsole, and said weight is formed so as
to be relatively thin at the toe portion and relative thick at the
heel portion.
3. A shoe sole comprising: a resilient outsole having a single
recess formed on an upper surface thereof, said recess extending in
a lengthwise direction from a toe portion of said outsole to a heel
portion of said outsole, wherein said recess has an outline that is
similar to an outline of said resilient outsole; and a single
integral weight comprising a resilient housing filled with a
mixture of metallic grains and a resilient material, said weight
having an outline that is similar to the outline of said resilient
outsole, and said weight fits in said recess, said weight being
formed so as to be relatively thin at the toe portion and
relatively thick at the heel portion, and an upper surface of said
weight is level with an upper surface of said resilient outsole,
wherein said housing comprises a container having an open top, and
a closure bonded to the container, and wherein a bottom surface of
said container is adhesively bonded in said recess of said outsole
to secure the weight therein, and said housing is shaped so as to
conform to the shape of said recess.
4. A shoe sole as claimed in claim 3, further comprising a midsole
bonded to the outsole, and an insole superposed on said
midsole.
5. A shoe sole as claimed in claim 4, wherein said insole is a
three-ply structure.
6. A shoe sole comprising: a resilient outsole having a single
recess formed on an upper surface thereof, said recess extending in
a lengthwise direction from a toe portion to a heel portion of said
resilient outsole, said recess having an outline that is similar to
an outline of said resilient outsole; and a single integral weight
inserted in said recess of said resilient outsole, said weight
extending continuously over a bottom surface of said recess, and
said weight comprising a mixture of a metallic material and a
resilient material, wherein said single weight fits in said recess
and has an outline that is similar to the outline of said resilient
outsole, and said weight is formed so as to be relatively thin at
the toe portion and relatively thick at the heel portion, wherein
said weight comprises a resilient housing filled with said mixture
of metallic material and resilient material, wherein said resilient
housing comprises a container having an open top, and a closure
bonded to the container, and wherein a bottom surface of said
container is adhesively bonded in said recess of said outsole in
order to secure the weight therein.
Description
BACKGROUND OF THE INVENTION
The present invention relates to shoe soles of training shoes,
walking shoes, business shoes, casual shoes and the like which can
apply a larger-than-normal load to leg muscles and strengthen the
lower half of the body of the wearer of the shoes while the wearer
of the shoes is walking or otherwise exercising.
Conventional training shoes for strengthening the lower half of the
body during walking are provided with a weight and the like
embedded in soles to increase the overall weight of shoes. For
example, U.S. Pat. No. 5,231,776 discloses a shoe having a
weight-retaining matrix of lattice grid structure molded to a sole,
each matrix being filled with metallic balls. Instead of such
metallic balls, a shoe disclosed in U.S. Pat. No. 5,758,435 is
provided with a shoe sole having weight chambers which are filled
with the weights comprising a mixture of metallic grains and
adhesives.
However, in the above conventional shoes, the operations of filling
metallic balls or weights into a large number of matrixes or
chambers are extremely troublesome. Furthermore, when the weight of
the metallic balls or weights varies in each matrix or chamber, the
overall balance of shoe soles is destroyed and walking comfort
deteriorates.
In Japanese Utility Model Publication No. 45-21005, there is
disclosed a shoe having a shoe sole comprising an outsole, a
midsole and an insole wherein a plurality of recesses are formed on
the upper surface of the midsole in the width direction of the sole
and parallel to one another in the lengthwise direction of the sole
and weights are embedded in the recesses. The weights comprise a
mixture of resilient materials such as natural rubber, synthetic
rubber or synthetic resin etc. and metallic grains. In
manufacturing such a shoe, the weights should be made in conformity
with the concave form of the recesses and each weight should be
embedded in a corresponding recess of the same form. Thus it is
extremely troublesome to embed the weights and the workability is
poor.
Furthermore, in Japanese Utility Model Application laid-open under
No. 56-103205, there is disclosed a shoe having a shoe sole
provided with a recess at the toe portion and at the heel portion
respectively and provided with a metallic weight embedded in the
respective recess. In this construction, embedding the weights is
comparatively easy. However, when the weight difference is large
between the two weights, the weight balance of the shoe is
destroyed and eventually an excessive load is applied to legs of
the wearer of such shoe, and as a result, the shoe may cause bodily
injury instead of strengthening the lower half of the body of the
wearer. In addition, since the weight is made of metal and is not
flexible, walking comfort deteriorates.
As mentioned above, conventional shoes in any structures have
merits and demerits. It is therefore an object of the present
invention to provide a shoe sole having good overall weight balance
and flexibility suitable for walking, while improving the
operational efficiency of embedding weights.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a shoe sole
including a resilient outsole having a single recess bored on the
upper surface and extending in the lengthwise direction from a toe
portion to a heel portion of the outsole. The recess has a similar
outline to the outline of the outsole, and a single weight
comprising a mixture of a resilient material and metallic grains is
embedded in the recess.
In such a shoe sole, the single weight can be easily embedded in
the single recess bored on the upper surface of the outsole after
being prepared in a separate manufacturing process, and the
workability of embedding the weight is improved. Since the weight
is formed with a mixture of a resilient material and metallic
grains, it has resilience to function as a shock absorber, so that
there is no need to adopt such shock absorbing materials such as
rubber sponges and the like. The metallic grains are made of iron,
stainless steel or the like having a large specific gravity and may
be granular, powder or flake in shape.
It is preferred that the single weight has a similar outline to the
outline of the outsole and fits in the recess having a similar
outline to the outline of the outsole, so that the weight can be
easily disposed at a well-balanced position in the outsole and that
the load of weight applied to the sole disperses widely. It is then
possible to maintain a proper weight balance of the shoe sole. The
resilient weight deforms when a load is applied thereto, but as the
recess is formed to fit over the entire sole of a foot, the
deformation of the weight occurs uniformly, so that weight balance
is maintained when the a load is applied the shoe sole.
It is also preferable that the weight is formed so as to be thin at
the toe portion and thick at the heel portion, so that the weight
can be easily bent from the toe portion. Thus, the flexibility of
the outsole is maintained inspite of the existence of the weight.
As the heel portion is formed so as to be thick, it receives firmly
the heel of the foot without causing excessive deformation.
Also, it is preferred that the weight comprises a resilient housing
and a mixture of a resilient material and metallic grains filled in
the housing.
There is also provided a shoe sole comprising a resilient outsole
having a single recess bored on the upper surface and extending in
the lengthwise direction from a toe portion to a heel portion of
the outsole and a single weight comprising a resilient housing and
a mixture of a resilient material and metallic grains filled in the
housing. The recess has a similar outline to the outline of the
outsole, and the single weight has a similar outline to the outline
of the outsole and fits in the recess. The weight is formed so as
to be thin at the toe portion and thick at the heel portion with an
upper surface that is level with an upper surface of the
outsole.
In case the upper surface of the weight is level with the upper
surface of the outsole, shoe components to be superposed on the
outsole are stably set without causing gaps therebetween, so that
the durability of the shoe is increased and no strange feelings are
experienced by the wearer.
Other features and objects of the present invention will become
apparent from the following description made with reference to the
accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a training shoe embodying
the shoe sole in accordance with the present invention;
FIG. 2 is a sectional view of the shoe sole;
FIG. 3 is a plan view of the outsole;
FIG. 4 is a sectional view in the lengthwise direction of the
outsole; and
FIG. 5 is a sectional view in the width direction of the
outsole.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a training shoe having an embodiment of a shoe sole
constructed in accordance with the present invention. The training
shoe comprises a shoe sole 1 to be brought into contact with the
sole of a foot and an upper 2 provided integrally with the shoe
sole 1. The shoe sole 1 comprises an outsole 3, a midsole 4 and an
uppermost insole 5 superposed one on another in this order from
below. A single recess 6 is bored on the upper surface extending in
a lengthwise direction from a toe portion to a heel portion of the
outsole 3, and a resilient weight 7 is embedded in the recess
6.
The upper 2 is made of synthetic fiber, synthetic leather or
genuine leather and has a mouth 8 through which a foot is inserted
and eyelets 9 through which a shoe lace 10 is passed. The degree of
the opening of the mouth 8 is adjustable by tightening the shoe
lace 10. On the heel side of the mouth 8, an ankle pad 11 made of
urethane foam is provided so as to protect the Achilles tendon of a
shoe wearer. Instead of the shoe lace 10, a fastening means having
resilient hook and loop fasteners may be available for adjustably
fixing the foot to a shoe.
The upper 2 is provided with an integral tongue 12 having an
urethane foam pad that is thicker than a conventional pad. The
thick tongue 12 will minimize shock and compression exerted on the
instep of a foot. It is thus possible to lighten a load extended on
an ankle.
The outsole 3 is made of a resilient thermoplastic rubber such as
EVA(ethylene-vinyl acetate copolymer), thermoplastic urethane
rubber and the like.
The bottom of the outsole 3 is formed in such a manner that the tip
of the toe portion rises and the portion extending from the toe
portion to the heel portion is flat and the rear end of the heel
portion is cut on a slant. The form of the bottom of the outsole 3
is not limited to the configuration described above. For example, a
shank may be formed between the toe portion and the heel portion
for walking shoes, business shoes and casual shoes.
The midsole 4 is made of a regular thin rubber, leather and the
like. The insole 5 has a three-ply structure having a total
thickness of 5 mm and comprising, for example, an EVA
(ethylene-vinyl acetate copolymer) sponge layer 5a, a foamed latex
layer 5b and a polyester substrate 5c laminated in this order from
below and bonded together with an adhesive. An insole used in an
ordinary training shoe with no added weights is less than 3 mm
thick. Using the midsole 4 and the insole 5, which has a thickness
larger than ordinary, provides enhanced shock absorbability and
walking comfort for the wearer.
As shown in FIG. 4 and FIG. 5, the upper surface of the outsole 3
is concave so as to form a recess 6 and a rising peripheral wall 20
is provided along the edge thereof. The recess 6 formed on the
upper surface of the outsole 3 has an outline that is similar to
the outline of the outsole 3. The bottom of the recess 6 has a
profile that slopes downward from the tip of the toe portion to the
center portion in the lengthwise direction and becomes flat toward
the heel portion and slopes upward toward the rear end of the heel
portion. Thus, the depth of the recess 6 is shallow at the toe
portion and deep at the heel portion. The recess 6 may be
integrally formed when molding the outsole 3 with a molding
machine, or formed with a die after the outsole 3 has been
molded.
The weight 7 has an outline that is similar to the outline of the
outsole 3 and fits in the recess 6 that is bored on the upper
surface of the outsole 3 and the weight is formed so as to be thin
at the toe portion and thick at the heel portion. The upper surface
of the weight 7 is level with the upper surface of the outsole 3
when embedded in the recess 6. It is thus easy to laminate other
shoe components on the outsole 3.
The weight 7 is a molded element which comprises a hollow housing
21 and a mixture of a resilient material 22 and metallic grains 23
filled in the housing 21. The housing 21 is formed so as to conform
to the concave shape or configuration of the recess 6, and the
housing comprises a container 21 a having an open top and a closure
21b. The housing 21 is filled with metallic grains 23 together with
the resilient material 22, so that they are not exposed externally
and are fixed stably in the housing 21. Thus, the metallic grains
23 do not shift during walking or exercising and the walking
comfort is not adversely affected.
The resilient material 21 is natural rubber, synthetic rubber,
elastomer, or any optional mixture thereof, for example, the
mixture of styrene-butadiene rubber, nitrile rubber, isoprene
rubber and barium sulfate as a filler. The filler has a large
specific gravity and occupies 50% of the mass of the weight 7. The
housing 21 may be formed of the same resilient material as the
resilient material 22 or formed of a different resilient material.
The metallic grains 23 may be made of iron, stainless steel and the
like. Iron grains are preferred from an economical point of view,
and nickel plating is preferred for preventing rust. Instead of
metallic grains 23, metallic powders or metallic flakes may also be
used.
The weight 7 may be produced as follows. First the container 21 a
having an open top is formed so as to conform to the concave shape
or configuration of the recess 6. Then the mixture of the resilient
material 22, in a fluid state, and the metallic grains 23 is poured
into the container 21 a to a level such that the mixture is near
the open top. It is preferred that the metallic grains 23 are
dispersed uniformly. After the container 21 a is capped with the
closure 21b, the housing 21 is formed by applying heat and pressure
to bond integrally the container 21 a and the closure 21b. The
mixture in the housing 21 sets therein and is integrated with the
container 21 a and the closure 21b. Thus, the weight 7 is produced
with the same shape as the concave shape or configuration of the
recess 6. The weight 7 is embedded in the recess 6 of the outsole
3. Adhesives may be used to fix the weight in the recess 6. The
upper 2 is cemented on the flat upper surface of the outsole 3
including the weight 7 which is embedded therein.
Furthermore, the upper 2 is stitched to the outsole 3. Thus, the
upper 2 is securely fixed to the outsole 3 so as to sustain the
weight of the outsole 3 and the durability thereof is enhanced. The
midsole 4 is laminated and bonded on the outsole 3 and subsequently
the insole 5 is superposed on the midsole 4 to complete a shoe. The
insole 5 is arranged so as to be detachable.
When a person walks in the shoes constructed in accordance with the
above, a load which is larger three or four times than when walking
in ordinary training shoes will act on the wearer's leg, and they
are trained and strengthened. Moreover, burning off excess fat is
accelerated and shape-up can be accomplished. Although the shoe
sole 1 is made heavier than ordinary training shoes, shocks applied
to feet and legs can be absorbed by the resilient weight 7 and
insole 5. Namely, due to the high cushioning property, shocks are
scarcely transmitted to feet and legs, and thus it is possible to
prevent injuries to feet and legs. During walking, the stepping
portion, that is, the region between the toe portion and the shank
of the shoe sole 1, is subjected to a bending force. However, the
weight 7 is pliable at the thin toe portion and the pliability of
the shoe sole is not reduced and thus the wearer can walk and run
smoothly and comfortably.
When the weight 7 is produced in a separate process, the weight of
the mixture is adjusted so as to be uniform with respect to all
shoes of the same size. Thus, the weight of the weight 7 can be
easily made uniform and the weight difference can be minimized,
which contributes the quality improvement of the shoe sole. It is
also possible to change the weight of the sole 1 without
difficulty.
The weight 7 is formed in conformity to the outline of the outsole
3 and the outlines of the outsoles 3 are similar to each other in
spite of the difference in size. Accordingly the weight 7 of a
common single size may be applicable to every size of outsole,
which contributes to the mass-productivity of the shoe sole 1.
Also, the recess 6 can be formed to conform to the weight 7 of a
common single size, so that mis-assembling of the weight 7 in the
recess 6 never occurs. Thus, the workability is extremely enhanced
and the manufacture's cost is also remarkably reduced.
The present invention is not limited to the above-described
specific embodiments but is subject to various changes and
modifications. For example, the weight may be formed of a double
structure such that the stepping portion, that is, the region
between the toe portion and the shank or a flat center portion, is
made of a resilient material with low rigidity and the remaining
portion is made of a resilient material with high rigidity. With
this arrangement, the stepping portion thereof becomes more
flexible, while the flexibility at the heel portion is restrained.
On the upper surface of the weight, a plurality of grooves may be
formed at the stepping portion thereof in the width direction, so
that the weight becomes flexible at the stepping portion. Such
grooves may be formed also in the lengthwise direction of the
weight, so that the toe portion of the weight can be easily
twisted. Instead of such grooves, the weight may be perforated so
as to be deformable.
According to the present invention as described above, the weight
can be easily embedded in the recess of the outsole. Furthermore,
the shape of the weight is formed to conform to the shape of the
recess, and thus the weight can be embedded in the recess without
errors. The construction of the weight contributes the
mass-productivity of the shoe sole and the manufacturing costs can
be reduced.
In addition, by making the stepping portion of the weight thin, the
flexibility of the weight is enhanced, so that the shoe sole having
walking comfort can be provided.
* * * * *